Rotating mechanism for rock-drills



(N0 Mcjwdel.)

I H. BALL.

ROTATING MEGHANISM FOR ROCK DRILLS.

No. 451,425. Patented Apr. 28, 1891.

WITNESSES IJVVEJV'TOfR /@WW, M6 M7 UNITED STATES ATENT Fume.

HARRY BALL, OF STAMFORD, ASSIGNOR OF ONEIIALF TO FREDERICK LENGGENHAGER, OF GLENBROOK, CONNECTICUT.

ROTATING MECHANISM FOR ROCK-DRILLS.

SPECIFICATION forming part Of Letters Patent No. 451,425, dated April 28, 1891.

Application filed August 25, 1890. Serial No. 362,960. (No model.)

To all whom it may concern:

Be it known that I, HARRY BALL, a citizen of the United States, residing at Stamford, in the county of Fairfield and State of Connecticut, have invented certain new and useful Improvements in Rotating Mechanism for Rock- Drills; and I do hereby declare the following to be afull, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to rock-drills operating either by steam or compressed air, and has for its object to provide novel mechanism for rotating the piston and piston-rod to which the drill (not shown) is attached in any ordinary or preferred manner, the effect of my present invention being to simplify the construction and reduce the number of parts, thereby cheapening the cost of production and'securing at the same time durability, non-liability to get out of repair, and

thoroughly effective operation in use,- the construction, moreover, being such that in the event of the breakage of any of the parts the broken parts may be removed and new ones substituted with but slight expense by any person capable of running a rock-drill, thus avoiding the necessity of going to a machineshop or stopping the drill but for a very short time.

For the sake of clearness I have omitted from the drawings all portions of the drill except such as are necessary to clearly illus trate the construction and operation of the rotating mechanism.

Figure 1 is a section of the cylinder and piston, also showing the rotating mechanism proper being in practice clamped together by longitudinal bolts (not shown) which pass through holes in the heads. (See Figs. 2, 3, and 4.)

5 denotes the piston, and G the piston-rod, which passes through an opening in cylinder-head 3, being in practice ordinarily made in two parts and provided with a recess to receive packing 7, said recess being closed by a screw-cap 8, through which the pistonrod passes. The piston is provided with a central longitudinal opening 9, which receives spirally-grooved rod 10 freely. At the upper end of the opening in the piston is a nut 11, which is preferably made of hardened steel, and which is provided with lugs 12 to engage the grooves in the rod.

Head 2 of the cylinder is provided with a socket 13 to receive the other end of rod 10, and with a recess 1%, which is concentric with the socket. This recess in practice is closed by a plate 15, which is provided with a central opening through which the rod passes, and is made the exact diameter of the bore of the cylinder. The plate is made to fit closely and lies partly in the bore of the cylinder and partly in a recess in head 2, adapted to receive it. This plate acts to effectually close this end of the piston against the passage of steam.

\Vithin the recess and secured rigidly to the rod is an eccentric 10, which is provided with a pin 17, extending outward from its periphery at a point slightly at one side of the longest radius of the eccentric.

In the present instance the parts are so organized as to produce a rotation of the piston and piston-rod during the downward movement'. 6., the movement toward the right. This requires that the pin be placed at the right of the greatest radius of the eccentric, as seen in the drawings. Should rotation of the piston and piston-rod be required during the upward 1novementi. 6., the movement toward the left-the pin would require to be placed at the left of the longest radius of the 5 eccentric, as will be fully explained.

Outside of the eccentric and lying within recess ll is a crescent-shaped piece 18, between the ends of which is an open space in which pin 17 lies.

19 is a notch in the inner side of the crescent-shaped piece, the object of which is to permit said piece to yield suflicicntly to allow t to be sprung into place over the eccentric. lhe perlphery of crescent-shaped piece 18 is r 5 concentric with recess 11 and with red 10, the

inner line of said crescent-shaped piece corresponding with the periphery of the eccentric. The operation is as as follows: Suppose the parts to be in the positions shown in Figs. 1 20 and 3. lVhcn the upward movementi. 6., the movement of the piston toward the left of the cylinder-takes place, pin 17 will on gage one end of the crescent-shaped piece, the right end, as shown in Fig. 3, and will carry said plecc wit-h it. It will be apparent in viewof the engagement of lugs 12 011 the piston with the spiral grooves of rod 10 that at each movement either the piston itself or the rod must rotate. In the position of the parts shown in Fig. 3 the piston moves straight upthat is, without rotationand the rod is rotated by the engagement of the lugs with the spiral grooves carrying the eccentric with it, and the latter, through the engagement of the pin with 3 5 the end of the crescent-shaped piece, carries the latter also, the rod, eccentric, and crescentshaped piece turning freely in recess 14. The instant the downward movement of the pistOll-t, 6., the movement toward the right- 4 commences, the spirally-grooved rod is necessarily turned in the opposite direction. This moves the eccentric in the opposite direction, moving the pin away from the end of the crescent-shaped piece with which it has been in engagement. The effect of this reverse movement of the eccentric is to carry the point in the periphery of the eccentric having the longest radius against the inner side of the crescent-shaped piece, springing the latter 5 outward and causing it to be locked tightly in recess 1i by friction. In fact, the rotary movement of the grooved rod in this direction is stopped almost instantly, so that as the piston moves downward it is necessarily retated through the engagement of the lugs with the grooves in the rod.

Having thus described my invention, I claim- 1. In a rock-drill, a piston having a longitudinal recess and lugs extending into said recess, in combination with a spirally-grooved rod which is adapted to enter the recess in the piston and is engaged by the lugs, an eccentric rigidly secured to said rod and having a pin projecting from its periphery at one side of the longest radius thereof, and a crescentshaped piece lying in a recess outside of the eccentric, one end of said piece in use being engaged by the pin, so that when the piston is moved in one direction it will rotate the rod, eccentric, and crescentshaped piece, and when moved in the opposite direction the longest radius of the eccentric will be forced against the crescent-shaped piece, springing the latter outward against the wall of the recess, thereby locking the eccentric and rod against rotation and causing a rotary movcment of the piston.

2. The combination, with the piston having longitudinal opening 9 and lugs 12, of spirallygrooved rod 10, engaging said opening and lugs, and having rigidly secured thereto an eccentric with a pin extending from its pcriphery at a point at one side of the longest radius, and a crescent-shaped piece lying out side of the eccentric, one of whose ends is engaged by the pin when the piston is moved in one direction, substantially as described.

3. The piston having an opening 9 and lugs 12, the piston-rod, and the cylinder having a head 3, through which the piston-rod slides, and a head 2, having a socket 13 and recess 11-, in combination with a spirally-grooved red, one end of which engages the lugs and opening in the piston, the other lying in socket 13, and an eccentric lying in recess 1%, said eccentric having a pin 17 at one side of the longest radius and a crescent-shaped piece 18 lying in said recess outside of the eccentric.

t. The cylinder, one of whose heads is provided with a socket 13 and recess 14, and the piston having a longitudinal opening, and a nut at the outer end thereof having inwardlyprojecting lugs, in combination with a rod having spiral grooves adapted to be engaged by the lugs and whose opposite end rests in the socket, an eccentric in the recess, which is rigidly secured to the rod and is provided with a pin 17, and a crescent-shaped piece lying in the recess outside of the eccentric, said parts acting as described, and for the purpose set forth.

In testimony whereof I affix my signature in presence of two witnesses.

HARRY BALL.

\Vit-ncsses:

RICHARD BOLSTER, BENJAMIN Lookwoon. 

